Solenoid valve mainly electricity as its energy, the current through the drive electromagnetic coil electromagnetic force, and then electromagnetic force through the control spring to control the valve. Of course, this spring can be used to control the closing and opening of the valve. The gas circuit can be opened when the coil is not energized, which is a normally closed valve, and the gas circuit can be opened when the fuel micro solenoid valve coil is not energized, which is a normally open valve.

The working principle of normally closed solenoid valve is that the coil is energized and the air loop is connected. Once the coil is powered off, the air loop is disconnected, equivalent to a "tap." The working principle of normally open solenoid valve is to energize the coil and break the gas road. Once the power is cut off, the coil is connected to the vent circuit, also known as "tapping".

Usually according to the continuous working time selection: normally closed, normally open or continuous power.

1. When the high-speed pneumatic solenoid valve needs to be opened for a long time, and the duration exceeds the closing time, normally open type should be selected.

2. If the opening time is short or the opening and closing time is short, select the normally closed mode.

3. However, some working conditions for safety protection, such as furnace flame monitoring, cannot be opened normally, but can be powered on for a long time.

Solenoid valve is a common automatic execution equipment. It has the characteristics of good performance, low price, easy installation and fast reaction speed. Because of these excellent characteristics, it has begun to occupy a large number of valve market, and is widely used in various fields.

Electric valve energy efficient, is gradually occupying the market. In industrial processes, valves are mainly used to control the movement and flow of various fluids, such as water, oil, chemical liquids and so on. Based on parameters such as temperature, pressure and flow rate. Factory commonly used control valves are pressure reducing valve, pneumatic constant temperature valve, solenoid valve constant temperature system, control valve constant temperature system, temperature control valve and so on. In the selection of various automatic valves, we should consider the type of heat engine, the required accuracy, the quality of the control valve, pressure drop, flow and its structure, failure rate, after-sales service, in order to achieve the purpose of economic and practical.